Osteoporosis: regulatory view.

Evaluation of drugs proposed for the prevention and treatment of osteoporosis is difficult. The Food and Drug Administration (FDA) has issued guidelines for the clinical investigation of drugs in this class. Estrogen has been approved for the treatment of postmenopausal osteoporosis. Administration of estrogen requires careful assessment of the risks and benefits for the individual patient. The smallest effective dose should be used. There are both potential risks and benefits for the concommitant administration of a progestin. Calcitonin has also been approved; however, the need for parenteral administration, the problem of antibody formation, and expense may limit the usefulness of the currently marketed preparations. Calcium has been recommended, but because it is considered a food supplement it has not been submitted to FDA for evaluation of its safety and efficacy as a drug in the treatment of osteoporosis. Other drugs under investigation include anabolic steroids, fluorides, vitamin D substances, biphosphonates, parathyroid hormone, and thiazides.